Third-order nonlinearity enhancement in an artificial Kerr medium through bulk intrinsic birefringence

Laser-induced circular birefringence measurements have been performed on a liquid suspension of polymer microellipsoids in order to study its optical nonlinearity as a function of the host liquid’s refractive index nh. The results show that the large values obtained for the χ_1221^(3) term (1.6 × 10^‐8 esu for nh = 1.330) can be explained with an intrinsic birefringence of the microellipsoids relative to their geometrical axes. The obtained values for the refractive indices are n_? = 1.391 and n_⊥ = 1.368.